SHFileOperation displays spurious errors in debug output

I'm using SHFileOperation to delete a folder tree. The function works correctly - the folder tree is deleted, return code is 0, and fAnyOperations aborted is zero. I am doubly-null-terminating the folder path. Yet in the debug output window I see errors like:

shell\osshell\lmui\ntshrui\dll\shrengine.cpp(1473)\ntshrui.dll!678E7855: (caller: 678E2F44) ReturnHr(1) tid(1308) 80070002 The system cannot find the file specified.

Exception thrown at 0x76EAB832 (KernelBase.dll) in GLStartD.exe: 0x000006BA: The RPC server is unavailable.

I just want to understand why I would see the errors, and if possible how to avoid them.